On the morning of September 11, 2001, two hijacked commercial jetliners struck the Twin Towers in Lower Manhattan, a third plane struck the Pentagon, and a fourth crashed in rural Pennsylvania. A total of 2.977 people were killed in the terrorist attacks. In the face of this unprecedented loss, the city of New York promised to rebuild Lower Manhattan as a lively neighborhood while honoring and maintaining the memory of this day. Thus began one of the largest reconstruction projects in New York City, a process that is still ongoing now, 23 years after the tragedy.
The World Trade Center opened for business in April 1973. The original complex in the Financial District of Lower Manhattan comprised 7 buildings, with the most distinctive ones being the Twin Towers. At 1,254 feet (382m), the North Tower became the tallest building in the world, after the placement of a steel beam on its last floor. The complex was designed by Minoru Yamasaki as lead architect and Emery Roth & Sons as associate architects. The attacks in 2001 were not the first attempts, as in 1993, a terrorist truck bomb was set off in the public parking garage of the World Trade Center, killing six and damaging the infrastructure of the building at 3 World Trade Center.
After the events of 9/11, the Twin Towers were not the only structures affected, all seven buildings of the World Trade Center were completely destroyed, along with the PATH train station that brought millions of commuters to Lower Manhattan. It took 99 days to extinguish the fires at ground zero. By May 30th, 2002, every piece of remaining steel was removed from Ground Zero, a cleanup process that took 8 months of continuous labor. The reconstruction process could now begin.
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Clad in Translucent Marble Slabs, The Perelman Performing Arts Center Opens in New York’s Ground Zero"Memory Foundations" Master Plan by Daniel Libeskind
By mid-2002, the Lower Manhattan Development Corporation has launched an open-design study to explore possibilities for rebuilding the World Trade Center. The seven finalists presented their ideas publicly in December 2002, and Daniel Libeskind was announced the winner in the following months. His master plan, titled Memory Foundations, included a memorial and museum dedicated to the victims, and 6 new skyscrapers surrounding the site.
The main challenge of the master plan was finding the balance between honoring the memory of the past tragedy and creating a dynamic neighborhood. As such, half of the 16-acre site was dedicated to public spaces, including the Memorial and Memorial Museum, with the remaining areas allocated for new high-rise developments.
"Reflecting Absence" Memorial Design by Michael Arad and Peter Walker
A second competition was held to develop the design of the memorial gardens. Out of the over 5,000 international entries, architect Michael Arad and landscape architect Peter Walker's proposal was chosen in January 2004. This design comprises two large waterfall pools occupying the original footprints of the North and South Towers. Surrounding these pools are bronze parapets inscribed with the names of the 2,983 victims, categorized by their locations during the attacks. The design emphasizes "absence made visible," with water cascading into central voids that can never be filled.
The Memorial Plaza, officially opened on September 11, 2011, also includes over 400 swamp white oak trees and the Survivor Tree, a Callery pear that endured the attacks and symbolizes resilience. Additionally, the 9/11 Memorial Glade, opened on May 30, 2019, in honor of those affected by post-attack toxins, features six stone monoliths incorporating remnant steel from the World Trade Center.
7 World Trade Center by David Childs of SOM
In May 2006, the first tower to be rebuilt was completed. Tower 7, or 7 World Trade Center, is the smallest of the new buildings proposed on site. Designed by David Childs of Skidmore, Owings & Merrill, the 52-story tower replaces the original 42-story structure, which was destroyed during the attacks. The new building uses low-iron glass for high reflectivity and incorporates stainless steel spandrels across its glass facade. Situated on a reduced footprint to allow for a nearby park, the building revises its predecessor's footprint to restore Greenwich Street.
4 World Trade Center by Fumihiko Maki
November 2013 saw the completion of the second tower at Ground Zero: the 4 World Trade Center (4 WTC), also known as 150 Greenwich Street. Designed by Pritzker Prize Laureate Fumihiko Maki, the 978 feet tall (298 meters)-tall structure serves as the headquarters of the Port Authority of New York and New Jersey. The building is replacing a 9-story structure destroyed during the September 11 attacks.
National September 11 Museum
The museum is part of the "Reflecting Absence" Memorial, commissioned to architects Michael Arad and Peter Walker, with Davis Brody Bond as the Executive Architect. Opened to the public on May 21, 2014, the 9/11 Memorial Museum offers a profound exploration of the 9/11 attacks and the 1993 bombing through its carefully designed architecture and exhibits. Entering through a Pavilion designed by Snøhetta, visitors descend into a space crafted by Davis Brody Bond, revealing remnants like the Survivors' Stairs. The museum's Foundation Hall features the Last Column and the slurry wall, symbols of resilience.
The museum's exhibitions delve deeply into the attacks' events and impacts. The main exhibition occupies the North and South Towers' footprints and includes "In Memoriam" for victims. Two additional galleries host photography and rotating exhibitions. The design is consistent with the original master plan by Daniel Libeskind, which called for the memorial to be 30 feet (9.1 m) below street level in a plaza, but it was the only finalist to disregard Libeskind's requirement that the buildings overhang the footprints of the Twin Towers.
One World Trade Center by SOM
November 3, 2014, marked the opening of One World Trade Center, also known as the Freedom Tower, which stands as the tallest building in the United States at 1,776 feet, a number chosen in reference to the year of the Declaration of Independence. Located on the northwest corner of the World Trade Center site, reclaimed from the Hudson River, the tower's podium shares the same footprint dimensions as the original Twin Towers, at 204 feet by 204 feet. Above the podium, the tower transitions from a square base to an aerodynamic octagonal form, culminating in a stainless steel parapet. At its top, One World Observatory offers 360-degree views of Lower Manhattan, adding to the tower's symbolic and functional significance.
The Oculus Transportation Hub by Santiago Calatrava
The Oculus, a transportation hub and shopping mall, opened on March 4, 2016, across the plaza from One World Trade Center. Designed by Santiago Calatrava, the Oculus began construction in 2004 and opened to the public in 2016. Designed as a freestanding structure on the southern edge of the "Wedge of Light" plaza, the Oculus connects urban spaces from City Hall Park to the gardens of the WTC Memorial and Battery Park. Its arched, elliptical form spans 350 feet in length and features upward-extending steel ribs, creating wing-like canopies that reach a height of 168 feet. These ribs, with glass in between, allow natural light to flood the space, symbolizing hope and vitality.
Liberty Park
Also in 2016, Liberty Park, a 1-acre elevated public park, opened. Located above the World Trade Center's Vehicular Security Center, the park is known as the location of St. Nicholas Greek Orthodox Church, which would be consecrated in 2022. The Koenig Sphere sculpture, which, despite being located in the plaza between the two towers, surprisingly survived the attack. In August 2017, the sculpture was returned and reinstalled in Liberty Park.
3 World Trade Center by Richard Stirk Harbour + Partners
Opened in June 2018, 3 World Trade Center rises to 1,079 feet (328m) as the second tallest building at the World Trade Center. Designed by architect Richard Rogers as part of Daniel Libeskind's Master Plan, the tower is distinguished by its steel exterior and unique K-shaped bracing. The building provides 2.5 million square feet (46 450 sqm) of office space across 80 stories, in addition to outdoor terraces and retail spaces.
St. Nicholas Greek Orthodox Church by Santiago Calatrava
The St. Nicholas Greek Orthodox Church and National Shrine replaced the original church destroyed in the September 11 attacks. Designed by Spanish architect Santiago Calatrava and administered by the Greek Orthodox Archdiocese of America, the church was scheduled to open in 2016, but financial issues delayed the opening. The church fully opened in December 2022.
Perelman Performing Arts Center by REX
The Perelman Performing Arts Center, known as PAC NYC, is a multi-space venue located at the northeast corner of the World Trade Center complex in Manhattan. Named after billionaire Ronald Perelman, who donated $75 million for its construction, the center spans approximately 90,000 square feet across three floors. Initially announced by the Lower Manhattan Development Corporation in 2004 as part of the post-9/11 World Trade Center redevelopment, the project faced delays and design changes. Designed by REX, with Davis Brody Bond as the Executive Architect, construction began below ground in 2017, and the above-ground structure was completed in 2020. The center opened on September 13, 2023.
2 World Trade Center by Foster + Partners (under construction)
World Trade Center 2 (2 WTC), also known as 200 Greenwich Street, is a planned skyscraper at the rebuilt World Trade Center complex in Manhattan, intended to replace the original 2 WTC. Designed by British architect Norman Foster, the new 82-story building will stand 1,345 feet tall, similar to the original South Tower's height. Foundation work was completed in 2013, but construction has not yet begun. The design features retail space, trading floors, and office areas, with a distinctive diamond-shaped roof.
On June 9, 2015, Wired reported that Bjarke Ingels of Bjarke Ingels Group (BIG) was redesigning Two World Trade Center after requests from developer Silverstein Properties. In January 2020, Norman Foster was brought back to update his original design, blending both architects' visions.
5 World Trade Center by KPF (under construction)
5 World Trade Center (5 WTC), located at 130 Liberty Street in Lower Manhattan, is a planned skyscraper developed by Silverstein Properties and Brookfield Properties. This new 910-foot-tall mixed-use tower will consist of 1.2 million square feet of residential space across 69 floors, with 360 units designated as permanent affordable housing. The base will feature retail, public amenities, and office space. Construction is set to begin in 2024, with completion expected by 2029. Originally planned as an office tower, it now offers rental units and has amenities organized into vertical neighborhoods. According to KPF, a pedestrian bridge links it to Liberty Park.
